0965bee0 |
1 | /* |
2 | * ldisc.c: PuTTY line discipline. Sits between the input coming |
3 | * from keypresses in the window, and the output channel leading to |
4 | * the back end. Implements echo and/or local line editing, |
5 | * depending on what's currently configured. |
6 | */ |
7 | |
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8 | #include <stdio.h> |
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9 | #include <ctype.h> |
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10 | |
11 | #include "putty.h" |
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12 | #include "terminal.h" |
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13 | |
0965bee0 |
14 | #define ECHOING (cfg.localecho == LD_YES || \ |
15 | (cfg.localecho == LD_BACKEND && \ |
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16 | (back->ldisc(LD_ECHO) || term_ldisc(term, LD_ECHO)))) |
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17 | #define EDITING (cfg.localedit == LD_YES || \ |
18 | (cfg.localedit == LD_BACKEND && \ |
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19 | (back->ldisc(LD_EDIT) || term_ldisc(term, LD_EDIT)))) |
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20 | |
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21 | static void c_write(char *buf, int len) |
22 | { |
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23 | from_backend(term, 0, buf, len); |
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24 | } |
25 | |
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26 | static char *term_buf = NULL; |
27 | static int term_buflen = 0, term_bufsiz = 0, term_quotenext = 0; |
28 | |
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29 | static int plen(unsigned char c) |
30 | { |
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31 | if ((c >= 32 && c <= 126) || (c >= 160 && !in_utf(term))) |
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32 | return 1; |
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33 | else if (c < 128) |
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34 | return 2; /* ^x for some x */ |
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35 | else |
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36 | return 4; /* <XY> for hex XY */ |
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37 | } |
38 | |
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39 | static void pwrite(unsigned char c) |
40 | { |
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41 | if ((c >= 32 && c <= 126) || (c >= 160 && !in_utf(term))) { |
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42 | c_write(&c, 1); |
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43 | } else if (c < 128) { |
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44 | char cc[2]; |
45 | cc[1] = (c == 127 ? '?' : c + 0x40); |
46 | cc[0] = '^'; |
47 | c_write(cc, 2); |
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48 | } else { |
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49 | char cc[5]; |
50 | sprintf(cc, "<%02X>", c); |
51 | c_write(cc, 4); |
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52 | } |
53 | } |
54 | |
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55 | static void bsb(int n) |
56 | { |
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57 | while (n--) |
58 | c_write("\010 \010", 3); |
59 | } |
60 | |
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61 | #define CTRL(x) (x^'@') |
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62 | #define KCTRL(x) ((x^'@') | 0x100) |
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63 | |
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64 | void ldisc_send(char *buf, int len, int interactive) |
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65 | { |
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66 | int keyflag = 0; |
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67 | /* |
68 | * Called with len=0 when the options change. We must inform |
69 | * the front end in case it needs to know. |
70 | */ |
71 | if (len == 0) { |
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72 | void ldisc_update(int echo, int edit); |
73 | ldisc_update(ECHOING, EDITING); |
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74 | return; |
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75 | } |
0965bee0 |
76 | /* |
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77 | * Less than zero means null terminated special string. |
78 | */ |
79 | if (len < 0) { |
80 | len = strlen(buf); |
81 | keyflag = KCTRL('@'); |
82 | } |
83 | /* |
0965bee0 |
84 | * Either perform local editing, or just send characters. |
85 | */ |
86 | if (EDITING) { |
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87 | while (len--) { |
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88 | int c; |
89 | c = *buf++ + keyflag; |
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90 | if (!interactive && c == '\r') |
91 | c += KCTRL('@'); |
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92 | switch (term_quotenext ? ' ' : c) { |
93 | /* |
94 | * ^h/^?: delete one char and output one BSB |
95 | * ^w: delete, and output BSBs, to return to last |
96 | * space/nonspace boundary |
97 | * ^u: delete, and output BSBs, to return to BOL |
98 | * ^c: Do a ^u then send a telnet IP |
99 | * ^z: Do a ^u then send a telnet SUSP |
100 | * ^\: Do a ^u then send a telnet ABORT |
101 | * ^r: echo "^R\n" and redraw line |
102 | * ^v: quote next char |
103 | * ^d: if at BOL, end of file and close connection, |
104 | * else send line and reset to BOL |
105 | * ^m: send line-plus-\r\n and reset to BOL |
106 | */ |
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107 | case KCTRL('H'): |
108 | case KCTRL('?'): /* backspace/delete */ |
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109 | if (term_buflen > 0) { |
110 | if (ECHOING) |
111 | bsb(plen(term_buf[term_buflen - 1])); |
112 | term_buflen--; |
113 | } |
114 | break; |
115 | case CTRL('W'): /* delete word */ |
116 | while (term_buflen > 0) { |
117 | if (ECHOING) |
118 | bsb(plen(term_buf[term_buflen - 1])); |
119 | term_buflen--; |
120 | if (term_buflen > 0 && |
121 | isspace(term_buf[term_buflen - 1]) && |
122 | !isspace(term_buf[term_buflen])) |
123 | break; |
124 | } |
125 | break; |
126 | case CTRL('U'): /* delete line */ |
127 | case CTRL('C'): /* Send IP */ |
128 | case CTRL('\\'): /* Quit */ |
129 | case CTRL('Z'): /* Suspend */ |
130 | while (term_buflen > 0) { |
131 | if (ECHOING) |
132 | bsb(plen(term_buf[term_buflen - 1])); |
133 | term_buflen--; |
134 | } |
135 | back->special(TS_EL); |
2a8a449c |
136 | /* |
137 | * We don't send IP, SUSP or ABORT if the user has |
138 | * configured telnet specials off! This breaks |
139 | * talkers otherwise. |
140 | */ |
141 | if (!cfg.telnet_keyboard) |
142 | goto default_case; |
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143 | if (c == CTRL('C')) |
144 | back->special(TS_IP); |
145 | if (c == CTRL('Z')) |
146 | back->special(TS_SUSP); |
147 | if (c == CTRL('\\')) |
148 | back->special(TS_ABORT); |
149 | break; |
150 | case CTRL('R'): /* redraw line */ |
151 | if (ECHOING) { |
152 | int i; |
153 | c_write("^R\r\n", 4); |
154 | for (i = 0; i < term_buflen; i++) |
155 | pwrite(term_buf[i]); |
156 | } |
157 | break; |
158 | case CTRL('V'): /* quote next char */ |
159 | term_quotenext = TRUE; |
160 | break; |
161 | case CTRL('D'): /* logout or send */ |
162 | if (term_buflen == 0) { |
163 | back->special(TS_EOF); |
164 | } else { |
165 | back->send(term_buf, term_buflen); |
166 | term_buflen = 0; |
167 | } |
168 | break; |
a5f3e637 |
169 | /* |
170 | * This particularly hideous bit of code from RDB |
171 | * allows ordinary ^M^J to do the same thing as |
172 | * magic-^M when in Raw protocol. The line `case |
173 | * KCTRL('M'):' is _inside_ the if block. Thus: |
174 | * |
175 | * - receiving regular ^M goes straight to the |
176 | * default clause and inserts as a literal ^M. |
177 | * - receiving regular ^J _not_ directly after a |
178 | * literal ^M (or not in Raw protocol) fails the |
179 | * if condition, leaps to the bottom of the if, |
180 | * and falls through into the default clause |
181 | * again. |
182 | * - receiving regular ^J just after a literal ^M |
183 | * in Raw protocol passes the if condition, |
184 | * deletes the literal ^M, and falls through |
185 | * into the magic-^M code |
186 | * - receiving a magic-^M empties the line buffer, |
187 | * signals end-of-line in one of the various |
188 | * entertaining ways, and _doesn't_ fall out of |
189 | * the bottom of the if and through to the |
190 | * default clause because of the break. |
191 | */ |
192 | case CTRL('J'): |
193 | if (cfg.protocol == PROT_RAW && |
194 | term_buflen > 0 && term_buf[term_buflen - 1] == '\r') { |
195 | if (ECHOING) |
196 | bsb(plen(term_buf[term_buflen - 1])); |
197 | term_buflen--; |
198 | /* FALLTHROUGH */ |
199 | case KCTRL('M'): /* send with newline */ |
200 | if (term_buflen > 0) |
201 | back->send(term_buf, term_buflen); |
202 | if (cfg.protocol == PROT_RAW) |
203 | back->send("\r\n", 2); |
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204 | else if (cfg.protocol == PROT_TELNET && cfg.telnet_newline) |
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205 | back->special(TS_EOL); |
206 | else |
207 | back->send("\r", 1); |
208 | if (ECHOING) |
209 | c_write("\r\n", 2); |
210 | term_buflen = 0; |
211 | break; |
212 | } |
213 | /* FALLTHROUGH */ |
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214 | default: /* get to this label from ^V handler */ |
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215 | default_case: |
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216 | if (term_buflen >= term_bufsiz) { |
217 | term_bufsiz = term_buflen + 256; |
218 | term_buf = saferealloc(term_buf, term_bufsiz); |
219 | } |
220 | term_buf[term_buflen++] = c; |
221 | if (ECHOING) |
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222 | pwrite((unsigned char) c); |
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223 | term_quotenext = FALSE; |
224 | break; |
225 | } |
226 | } |
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227 | } else { |
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228 | if (term_buflen != 0) { |
229 | back->send(term_buf, term_buflen); |
230 | while (term_buflen > 0) { |
231 | bsb(plen(term_buf[term_buflen - 1])); |
232 | term_buflen--; |
233 | } |
234 | } |
235 | if (len > 0) { |
236 | if (ECHOING) |
237 | c_write(buf, len); |
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238 | if (keyflag && cfg.protocol == PROT_TELNET && len == 1) { |
239 | switch (buf[0]) { |
240 | case CTRL('M'): |
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241 | if (cfg.protocol == PROT_TELNET && cfg.telnet_newline) |
242 | back->special(TS_EOL); |
243 | else |
244 | back->send("\r", 1); |
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245 | break; |
246 | case CTRL('?'): |
247 | case CTRL('H'): |
248 | if (cfg.telnet_keyboard) { |
249 | back->special(TS_EC); |
250 | break; |
251 | } |
252 | case CTRL('C'): |
253 | if (cfg.telnet_keyboard) { |
254 | back->special(TS_IP); |
255 | break; |
256 | } |
257 | case CTRL('Z'): |
258 | if (cfg.telnet_keyboard) { |
259 | back->special(TS_SUSP); |
260 | break; |
261 | } |
262 | |
263 | default: |
264 | back->send(buf, len); |
265 | break; |
266 | } |
267 | } else |
268 | back->send(buf, len); |
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269 | } |
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270 | } |
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271 | } |